I've never made an actual pic of me a profile picture & on some questions I get around 30 answers(without featuring it).
There are certain female users on here who use fake profile pics of other girls, attractive girls, and guys on here kiss their ass and line up to answer their questions. So the girls will get 50+ answers instantly. It does happen
I haven't asked any questions and I never really paid that much attention to the volume of answers per question and how that correlates to certain factors such as the asker's pictures and the difficulty of the question.
Speaking or myself, I don't look at the profile picture much when answering a question. I answer things that grab my interest. I'm here to be entertained just as much as I'm here to help.
I agree with PoeticNinja in a sense, easy questions do get more answers, but I do find guys like answering questions from girls they find attractive since they think it gets them noticed and they like to suck up to them.
Personally I answer questions based on the question alone. I have never really looked at the persons picture when reading the question. That is just me though.
I average about 15 answers per question and I always post anonymously. I think it comes down to the relevance of the question to most people. Like a lot of the questions I ask are not specific to a situation I'm facing (Ex. Why doesn't he like me?)...rather, I ask questions about gender in general(Guys, which is your favorite female body part?... lol). General questions like that have more relevance to people and therefore more will answer.
I will say though that I used to have a picture of myself on here and I got 75 answers on one question. lol So maybe it does help a little. = )